Work

Effect of organic electroactive crystallites in a dielectric matrix on the electrical properties of a polymer dielectric

Year: 2023

Type: article

Abstract: The effects of inserting chargeable \ensuremath{\alpha}-quaterthiophene ($\ensuremath{\alpha}4T$) crystallites in polystyrene (PS) multilayers used as a transistor gate and capacitor dielectric were investigated. X-ray diffraction, scanning electron microscopy with energy-dispersive x-ray spectroscopy, and confocal microscopy indicated the formation of $\ensuremath{\alpha}4T$ crystallites in the PS matrix. A modified saturation-regime current-voltage relationship was used to estimate organic field-effect transistor (OFET) threshold voltage ${V}_{\mathrm{TH}}$ shifting, and in turn the quantities of stored charge that were observed as a result of dielectric charging. The crystallites increased the maximum charge-storage capacity as well as the charge-retention capability of the dielectrics. Kelvin probe force microscopy showed that charges were localized near the $\ensuremath{\alpha}4T$ crystallites upon charging. Trilayer experiments validated the charge-retention improvement of $\ensuremath{\alpha}4T$ crystallite-embedded PS dielectrics. The crystallites also improved breakdown characteristics in PS used as a capacitor dielectric, suggesting their application to storage capacitors in addition to OFET logic.

Source: Physical Review Materials

DOI: 10.1103/physrevmaterials.7.065003